Hi guys,
Need help , cannot find a solution to our misfire problem,the motor seems like it leans out and it pops and I lose power, the motor runs up to 6500 in 1st to 6000 in second and third , the motor is a 383 stroker ,victor intake, holley 750 dbl, msd hei and wires, hyfire 6 ignition ,comp cam xe294h cam good for 2800 to 7000, hooker super comp hedders, motor is bluprinted and has world products angle plug heads, 4400 stall ,th350 ,trans brake. ford 9 inch with 411 gears,
Here’s what we have done ,,had the problem last year and could not figure it out,, so we replaced the heads ,the ignition system ,plugs, pulled the cover and degreed the cam again and found it spot on, we checked firing order, timing, valve lash , changed jets in the carb ,checked secondary operation, we are stumped, some of you have given great advice in the past and we thank you,, we are going nuts here ,, on the good side the thing still ran high 11’s with the problem ,, any and all solutions would be greatly appreciated, thanks
charles

When, where, what RPM does it pop and lose power?

It starts to pop at about 6500 in first and 6000 in 2nd and third,,it sounds like a all engine not out the back of the exhaust like a back fire, power falls off fast as soon as the popping starts,,replaced the secondaries today with 80 jets and problem still there,,thanks
Charles

thanks for the reply,,found out the valves were adjusted wrong,,turned them down 1/8 turn and the motor reved to 7500 no popping,,headed to Byron Dragway on Sat, keep you posted,,
Charles

I had a similar problem with my Vega it sounded like I was floating the valves so I checked seat pressure and it was a bit low. So I replaced springs and still had the problem. So I asked some guys on line (www.promodsource.com) I had a 7al2 msd ignition and they told me to tighten my spark plug gap to between 0.025 - 0.028 and the problem went away. It's worth a try to see if this is your problem. It cost nothing to close up the gap, which is always good!